The battle between the two independent television stations in the Orlando-Daytona Beach-Melbourne market is heating up as the underdog, WMOD- Channel 43, moves into a stronger fighting position.

Channel 43 and its major competitor, WOFL-Channel 35, estimate they take in about 20 percent of the market's television advertising dollars -- roughly $94 million -- and they fight the three network affiliates as well as each other for more.

WOFL-Channel 35, the older of the two stations, has always had a leg up. On the air since October 1979, the station was bought in 1983 by Meredith Corp., making it the fourth station in the market to be bought by a large outside communications company.

Meredith, a Des Moines-based broadcasting and publishing company, had revenues of $327.2 million in 1984. The strength of the company enabled WOFL to have a healthy advertising budget and to buy quality programming. The station captures about 9 percent of the market's viewing audience.

WMOD, on the other hand, has won only a 3 percent market share since going on the air in 1982. At the time, the station was owned by Southern Broadcasting Corp., whose investors included former congressman Lou Frey of Winter Park.

Last June, the station was purchased by Asbury Park Press in Asbury Park, N.J., for $3.5 million in cash and $3.5 in assumed debt. The company, which owns New Jersey's third-largest newspaper, the Asbury Park Press, is nowhere near the size of Meredith Corp., but it is strong enough to make a greater investment in the station.

First, of course, the company relieved the station of its debt, which also enabled program director Paul Williamson to complete the acquisition of some programming that had been stalled. ''The new management allowed us to execute deals we weren't able to complete, '' Williamson said. ''They paid off debts remaining from Southern Broadcasting and said, 'Go ahead and secure this product, this product and this product for 1986-1987.' ''

The new owners also brought in a new general manager for the station, Carlo Anneki. Anneki shuttles between WMOD and the company's other TV property, an independent station in Vineland, N.J. He was formerly station manager of independent Los Angeles TV station KTLA, which Chicago-based Tribune Co. bought last spring for a record $510 million.

Probably the main difference under the new management is that for the first time, WMOD has an advertising budget. Nancy Grossbart, the station's promotion manager for the past three years, said her budget had increased by almost 400 percent. ''They (the old management) were in trouble. They were giving me some money but certainly not enough.''

WMOD's new promotional campaign began airing Jan. 27 with spots on the station featuring the slogan ''Don't stay home without us.'' The same slogan is at the center of radio spots airing on 14 stations in the Orlando, Melbourne and Daytona Beach markets. In addition, 90 outdoor boards touting the station's early evening lineup and its Best of Carson show have been placed in the area.

Even the competition is laudatory. Chris Wolfe, director of advertising and promotions at WOFL, said, ''I like what they're doing now because it's so much more colorful, more pleasing to the eye.''

Asked if WOFL was going to launch a counterattack, Wolfe said the station's print advertising budget already has doubled in the past two years. ''The station, ever since it was taken over by Meredith, has assumed a position of strong advertising and promotion,'' Wolfe said. ''We're spending more now than we've ever spent before. We expect it (the budget) to get larger because of the competition in the market.''

Wolfe is not just referring to WMOD. Four new stations have been licensed by the Federal Communications Commission that could begin broadcasting in this market within the next three to five years. In December, Cablevision of Central Florida began carrying WGN of Chicago, an independent ''superstation'' along the lines of WTBS in Atlanta, which was already carried by the cable systems in the market.

Both stations' programming is similar in that they counterprogram the networks. Both WMOD and WOFL run about five hours a day of children's programming -- in the early morning and in the after-school afternoon hours. They both run syndicated half-hour comedies. Where they differ is in the amount of movies shown.

WMOD has tried to position itself as the market's ''free movie channel,'' and that strategy has not changed under new management. The station broadcasts movies every night at 8 and 11:30. Its movie library has more than 3,500 titles.

WOFL has a movie library almost as large, but during weeknight prime-time hours, the station broadcasts strip programming, or five nights a week of the same show. Hart to Hart and Quincy are the current offerings between 8 and 10 p.m.